Negative pressure wound closure device

ABSTRACT

The present invention relates to a negative pressure wound closure system and methods for using such a system. Preferred embodiments of the invention facilitate closure of the wound by preferentially contracting to provide for movement of the tissue. Preferred embodiments can utilize tissue grasping elements to apply a wound closing force to the tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/415,539, filed Jan. 16, 2015, entitled NEGATIVE PRESSURE WOUNDCLOSURE DEVICE, which is a U.S. national stage application ofInternational Patent Application No. PCT/US2013/050619, filed Jul. 16,2013, which claims the benefit of U.S. Provisional Application No.61/672,225, filed Jul. 16, 2012, entitled NEGATIVE PRESSURE WOUNDCLOSURE DEVICE, U.S. Provisional Application No. 61/771,732, filed Mar.1, 2013, entitled NEGATIVE PRESSURE WOUND CLOSURE DEVICE, and U.S.Provisional Application No. 61/780,629, filed Mar. 13, 2013, entitledNEGATIVE PRESSURE WOUND CLOSURE DEVICE. The contents of theaforementioned applications are hereby incorporated by reference intheir entireties as if fully set forth herein. The benefit of priorityto the foregoing applications is claimed under the appropriate legalbasis, including, without limitation, under 35 U.S.C. § 119(e).

BACKGROUND OF THE INVENTION Field of the Invention

This application describes embodiments of apparatuses, methods, andsystems for the treatment of wounds, specifically to aid in the closureof large wounds, in conjunction with the administration of negativepressure.

Description of the Related Art

Negative pressure wound therapy has been used in the treatment ofwounds, and in many cases can improve the rate of healing while alsoremoving exudates and other deleterious substances from the wound site.

Abdominal compartment syndrome is caused by fluid accumulation in theperitoneal space due to edema and other such causes, and results ingreatly increased intra-abdominal pressure that may cause organ failureeventually resulting in death. Causes may include sepsis or severetrauma. Treatment of abdominal compartment syndrome may require anabdominal incision to permit decompression of the abdominal space, andas such, a large wound may be created onto the patient. Closure of thiswound, while minimizing the risk of secondary infections and othercomplications, and after the underlying edema has subsided, then becomesa priority.

Other large or incisional wounds, either as a result of surgery, trauma,or other conditions, may also require closure. For example, woundresulting from sterniotomies, fasciotomies, and other abdominal woundsmay require closure. Wound dehiscence of existing wounds is anothercomplication that may arise, possibly due to incomplete underlyingfascial closure, or secondary factors such as infection.

Existing negative pressure treatment systems, while permitting eventualwound closure, still require lengthy closure times. Although these maybe combined with other tissue securement means, such as sutures, thereis also a risk that underlying muscular and tissue fascial tissue is notappropriately reapproximated so as to permit complete wound closure.Further, when foam or other wound fillers are inserted into the wound,the application of negative pressure to the wound and the foam may causeatmospheric pressure to bear down onto the wound, compressing the foamdownward and outward against the margins of the wound. This downwardcompression of the wound filler slows the healing process and slows orprevents the joining of wound margins. Accordingly, there is a need toprovide for an improved apparatus, method, and system for the treatmentand closure of wounds.

SUMMARY OF THE INVENTION

Embodiments of the present invention relate to negative pressure woundclosure devices, methods, and systems that facilitate closure of awound. The devices, methods, and systems may operate to reduce the needfor repetitive replacement of wound filler material currently employedand can advance the rate of healing. The devices, methods, and systemsmay be simultaneously used with negative pressure to remove woundfluids.

In one embodiment, a wound closure device comprises:

-   -   a stabilizing structure comprising a plurality of planar support        structures, each planar support structure comprising a first        plurality of beams intersecting with a second plurality of        beams, the plurality of planar support structures being arranged        parallel to one another;    -   a plurality of spring elements joining adjacent planar support        structures, the plurality of spring elements providing for        compression of the stabilizing structure so that the planar        support structures come closer to one another.

In some embodiments, the beams are rigid. In some embodiments, the firstplurality of beams intersects with the second plurality of beams at aright angle. Some embodiments may provide for each planar supportstructure to be substantially rigid within the plane of the supportstructure. In further embodiments, the planar support structurecomprises one or more standoffs located on an outer plane or perimeter.In further embodiments, the standoffs are provided with one or moretissue anchors configured to engage tissue placed into contact with thedevice. In some embodiments, a first plurality of spring elements islocated in a first plane perpendicular to the planar support structures,and a second plurality of spring elements is located in a second planeperpendicular to both the first plane and to the planar supportstructures. Some embodiments may provide for the first plurality ofspring elements being located in a first plurality of parallel planes,the first plurality of parallel planes including the first plurality ofrigid beams, and wherein the second plurality of spring elements arelocated in a second plurality of parallel planes, the second pluralityof parallel planes including the second plurality of rigid beams. Someembodiments may provide spring elements comprising V-shaped members. Insome embodiments, each planar support structure is identical. In someembodiments, a porous material such as foam surrounds one or more of theplanar support structures. In further embodiments, the porous materialsurrounds the entire device. In some embodiments, the stabilizingstructure comprises 2, 3, 4, 5 or more parallel planar supportstructures, with spring elements provided between each. In someembodiments, there may be an identical arrangement of spring elementsbetween each of the planar support structures.

Another embodiment provides for a stabilizing structure comprising aplurality of cells provided side-by-side in a plane, each cell definedby one or more walls, each cell having a top end and a bottom end withan opening extending through the top and bottom ends in the directionperpendicular to the plane; wherein the stabilizing structure isconfigured to collapse significantly more within the plane than alongthe direction perpendicular to the plane.

In some embodiments, the stabilizing structure is constructed from amaterial selected from the group consisting of silicone, rigid plastics,and foam. In some embodiments, the cells are identical; in otherembodiments, one or more of the cells are differently shaped from theremaining ones. The plane may extend in a horizontal direction. In someembodiments the walls may extend in a vertical direction. In someembodiments, the walls adjoin to adjacent cells. In some embodiments,the shape of each cell is selected from the group consisting of square,diamond, oblong, oval, and parallelepiped. In some embodiments, at leastone wall of each cell includes a notch or a hole. In some embodiments,at least one wall of each cell is configured to fold against anotherwall of the cell. Further embodiments may provide for each cell to beconnected to an adjacent cell by a joint, wherein the joints are moreflexible than the walls. Some joints may be more flexible than otherjoints in the same cell. The stabilizing structure may comprise cellsthat are more collapsible in a first direction along the plane than in asecond direction at an angle to the first direction along the sameplane. Sometimes the second direction may be perpendicular to the firstdirection. The stabilizing structure may comprise a plurality of firststrips extending in a first direction, and a plurality of intersectingstrips extending in a second direction perpendicular to the firstdirection, wherein the structure is collapsible in the first and seconddirections.

In some embodiments, the one or more walls further comprise an insertdisposed therein. The insert may be more rigid than the one or morewalls, and may be insertable into a preformed pocket within the one ormore walls. In some embodiments, the stabilizing structure comprises oneor more inserts, and wherein each of the one or more walls are moldedaround an individual insert. The insert may have a rectangularconfiguration. The insert may have a rectangular configuration with twonotches formed thereupon. In some embodiments, the insert comprises oneor more longitudinal grooves extending in the direction of the plane.The insert may further comprise one or more holes disposed therethrough.In some embodiments, the holes are arranged in a 6×6 pattern. The one ormore holes may be disposed on an edge of the insert.

In other embodiments, a stabilizing structure sized to be inserted intoa wound, comprises:

-   -   at least one top strip extending in a first direction, the top        strip comprising at least one notch extending partly        therethrough and opening on a bottom side of the top strip;    -   at least one bottom strip extending in a second direction, the        bottom strip comprising at least one notch extending partly        therethrough and opening on a top side of the bottom strip;    -   wherein the at least one top strip and bottom strip are        configured to be movably interlocked together by placing the        notch on the top strip over the notch on the bottom strip, and    -   wherein the at least one top strip and the at least one bottom        strip are configured to preferentially collapse along a first        plane defined by the first and second directions, while        remaining movably interlocked and substantially not collapsing        along a third direction perpendicular to the first plane.

Additional embodiments provide for the at least one notch on the topstrip and the at least one notch on the bottom strip to be dimensionedsuch that, when movably interlocked together, the top strip does notextend substantially above the bottom strip in the third direction. Infurther embodiments, the stabilizing structure comprises at least twotop strips and at least two bottom strips so as to form at least onequadrilateral space bounded by two top strips and two bottom strips.

Embodiments of the wound closure device disclosed herein may alsocomprise a porous material surrounding the entire stabilizing structure.The porous material may be foam. In some embodiments, porous materialsmay surround or be within each cell, quadrilateral space or otherinterior portions of the stabilizing structure. In some embodiments, thestabilizing structure may be insertable into a sock or enclosure formedof porous material such that the porous material covers at least aportion of an outer perimeter of the stabilizing structure. In someembodiments, separate porous material layers may be provided above,below, or on both upper and lower layers of the stabilizing structure.

In other embodiments, a stabilizing structure for insertion into a woundcomprises:

-   -   at least one top strip extending in a first direction;    -   at least one bottom strip extending in a second direction;    -   wherein the at least one top strip and bottom strip are        configured to be movably interlocked using an interlock        mechanism, and    -   wherein the at least one top strip and the at least one bottom        strip are configured to preferentially collapse along a first        plane defined by the first and second directions, while        remaining movably interlocked and substantially not collapsing        along a third direction perpendicular to the first plane.

In some embodiments, the interlock mechanism comprises: one of the atleast one top strip or bottom strip comprising two parallel claspsextending in the third direction; the other of the at least one topstrip or bottom strip comprising a projection extending in the thirddirection; and wherein the two parallel clasps rotatably engage with theprojection so as to rotate about the projection in the first plane whileremaining substantially fixed in the third direction. In someembodiments, the interlock mechanism comprises: one of the top strip orthe bottom strip comprising a projection with an enlarged distal end,the other of the top strip or bottom strip comprising a cup-shapedmember configured to receive the enlarged distal end of the projectiontherein; and wherein the top strip and bottom strips are rotatablyengaged so as to rotate about the projection in the first plane withoutdisengaging in the third direction. In some embodiments, the interlockmechanism comprises: one of the at least one top strip or bottom stripcomprising four clasps disposed at perpendicular angles to each otherextending in the third direction; the other of the at least one topstrip or bottom strip comprises a projection extending in the thirddirection; and wherein the two parallel clasps rotatably engage with theprojection so as to rotate about the projection in the first plane whileremaining substantially fixed in the third direction. Some embodimentsmay also comprise an uncompressed volume defined by the height of thestabilizing structure and the area of the stabilizing structure in thefirst plane when the first and second directions defined by the at leastone top strip and bottom strip are at perpendicular angles to eachother, and wherein the stabilizing structure, when compressed, defines acompressed volume that is at least 15% smaller than the uncompressedarea.

Additional embodiments provide for the top strip comprising at least onenotch extending partly therethrough and opening on a bottom side of thetop strip, and the bottom strip comprising at least one notch extendingpartly therethrough and opening on a top side of the bottom strip. Insuch an embodiment, the interlock mechanism places the notch on the topstrip over the notch on the bottom strip. In some embodiments, the atleast one notch on the top strip and the at least one notch on thebottom strip to be dimensioned such that, when movably interlockedtogether, the top strip does not extend substantially above the bottomstrip in the third direction. In further embodiments, the stabilizingstructure comprises at least two top strips and at least two bottomstrips so as to form at least one quadrilateral space bounded by two topstrips and two bottom strips.

In some embodiments, a stabilizing structure is provided for insertioninto a wound, comprising a plurality of elongate strips arranged inparallel (or generally in parallel), and a plurality of interveningmembers connecting the elongate strips, wherein the plurality ofintervening members are configured to pivot relative to the strips toallow the plurality of elongate strips to collapse relative to oneanother; wherein the intervening members between a first strip and asecond strip are configured to pivot independently of the interveningmembers between a second strip and a third strip.

In certain embodiments, the intervening members are connected to theelongate strips via at least one joint. In particular embodiments, thejoint is a hinge. In some embodiments, the hinges are configured tocollapse in one direction. In particular embodiments, the joints areconfigured to restrict the movement of the intervening members. Incertain embodiments, the elongate strips are rigid. In certainembodiments, the elongate strips are configured to bend along theirlength. In some embodiments, the elongate strips can be constructed froma material selected from the group consisting of silicone, rigidplastics, semi-rigid plastics, biocompatible materials, flexible plasticmaterials, composite materials, and foam. In some embodiments, theintervening members are constructed from a material selected from thegroup consisting of silicone, rigid plastics, semi-rigid plastics,biocompatible materials, flexible plastic materials, compositematerials, and foam.

In some embodiments, the stabilizing structure comprises a plurality ofintervening members between adjacent elongate strips to define a row ofcells between each pair of adjacent elongate strips. In someembodiments, the cells are in the shape of a diamond. In particularembodiments, the cells in a row between adjacent elongate strips areconfigured to collapse together as the adjacent strips collapse relativeto one another. In some embodiments, the rows of cells between adjacentstrips are configured to collapse in a first direction, and one or morerows of cells between adjacent strips are configured to collapse in asecond direction opposite the first direction. In some embodiments, allof the rows of cells of the stabilizing structure are configured tocollapse in the same direction.

In some embodiments, the intervening members between the first strip andthe second strip are offset relative to intervening members between thesecond strip and the third strip. In certain embodiments, foam surroundsthe elongate strips and the intervening members. In some embodiments,foam is contained between adjacent elongate strips.

In certain embodiments, the intervening members comprise panels. Inother embodiments, the intervening members comprise a plurality of barsconfigured to pivot relative to the elongate strips, and a plurality ofpins connecting the elongate strips to the bars. In some embodiments, aplurality of stops is configured to restrict the rotational movement ofthe pins.

The embodiments disclosed herein may also comprise a drape configured tobe placed over the wound closure device or stabilizing structure onceinserted into a wound so as to create a fluid-tight seal on the skinsurrounding the wound. Embodiments may also comprise a source ofnegative configured to be connected to the wound, and other associatedapparatuses.

Further embodiments provide for methods of closing a wound, comprising:

-   -   placing a wound closure device or stabilizing structure such as        described herein within a wound;    -   sealing the wound with a fluid-tight drape;    -   fluidically connecting the wound to a source of negative        pressure; and    -   applying negative pressure to the wound via the source of        negative pressure.

Further embodiments may provide for removing fluid from the wound site.In some embodiments, the wound closure device or stabilizing structureis placed into the wound such that the direction of collapse orcompression of the wound closure device or stabilizing structure isparallel or substantially parallel with the surface of the skin. In someembodiments, the application of negative pressure causes the woundclosure device or stabilizing structure to at least partly collapse.Further, the wound closure device or stabilizing structure may be atleast partly collapsed or compressed prior to inserting the stabilizingstructure into the wound. In some embodiments, the wound closure deviceor stabilizing structure is capable of collapse or compression to 40% orless, 30% or less, 20% or less, 10% or less or even 5% or less of one ofits original dimensions (e.g., along one of its lengths). Someembodiments provide for reducing the wound area by at least 50% upon theapplication of negative pressure.

Additional embodiments of a negative pressure wound closure system maycomprise:

-   -   a stabilizing structure such as described herein;    -   a drape sized and configured to be placed over the stabilizing        structure and to form a substantially fluid-tight seal against a        region of skin surrounding the wound; and    -   a source of negative pressure in fluid communication with the        wound.

Other embodiments of wound closure devices, stabilizing structures andassociated apparatuses are described below.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will be apparentfrom the following detailed description of the invention, taken inconjunction with the accompanying drawings of which:

FIG. 1 illustrates an embodiment of a negative pressure treatmentsystem.

FIGS. 2A-B are before and after photographs of experiments performed todetermine the efficacy of embodiments of wound closure devices.

FIGS. 3A-D illustrate different views of embodiments of a wound closuredevice comprising a stabilizing structure.

FIGS. 4A-E illustrate different views and photographs of embodiments ofa wound closure device comprising a stabilizing structure.

FIGS. 5A-B, 6A-B, and 7A-B are before and after photographs ofexperiments performed to determine the efficacy of certain embodimentsof wound closure devices.

FIGS. 8A-E illustrate additional embodiments of a wound closure devicecomprising a stabilizing structure.

FIGS. 9A-C illustrate an embodiment of a stabilizing structuremanufactured from felted foam.

FIGS. 10A-B are photographs of further embodiments of wound closuredevices comprising a porous wound filler material.

FIGS. 11A-B, 12, 13, 14, 15, and 16A-B illustrate additional embodimentsof wound closure devices comprising a stabilizing structure.

FIGS. 17A-B, 18A-B are before and after photographs of experimentsperformed to determine the efficacy of certain embodiments of woundclosure devices.

FIG. 19 is a photograph of an experiment performed to determine theefficacy of certain embodiments of wound closure devices.

FIGS. 20A-B are photographs of experiments performed to determine theefficacy of certain embodiments of wound closure devices.

FIGS. 21A-E are photographs of various embodiments of stabilizingstructures comprising inserts disposed therein.

FIGS. 22A-F illustrate various embodiments of inserts that may be usedin stabilizing structures.

FIGS. 23A-F illustrate multiple views of an embodiment of a stabilizingstructure.

FIGS. 24A-D illustrate multiple views of an embodiment of a stabilizingstructure.

FIGS. 25A-E illustrate multiple views of an embodiment of a stabilizingstructure.

FIG. 26 schematically illustrates an embodiment of a stabilizingstructure.

FIG. 27A illustrates a top view of an embodiment of an oval shapedstabilizing structure.

FIG. 27B illustrates a top view of an embodiment of an oval shapedstabilizing structure with foam.

FIGS. 28A-B illustrate embodiments of methods for closing a wound.

FIGS. 29A-C illustrate multiple views of an embodiment of a stabilizingstructure.

FIGS. 30A-G illustrate multiple views of an embodiment of a stabilizingstructure.

FIG. 31 illustrates one embodiment of a hinged stabilizing structure forclosing a wound.

FIG. 32 illustrates an embodiment of a fully flexible stabilizingstructure.

FIG. 33 illustrates one embodiment of a stabilizing structure for awound.

FIG. 34 illustrates an embodiment of a stabilizing structure for a woundcut from a roll.

FIG. 35 illustrates an embodiment of a stabilizing structure having anoval shape.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments disclosed herein relate to apparatuses and methods oftreating a wound with reduced pressure, including pump and wounddressing components and apparatuses. The apparatuses and componentscomprising the wound overlay and packing materials, if any, aresometimes collectively referred to herein as dressings.

It will be appreciated that throughout this specification reference ismade to a wound. It is to be understood that the term wound is to bebroadly construed and encompasses open and closed wounds in which skinis torn, cut or punctured or where trauma causes a contusion, or anyother superficial or other conditions or imperfections on the skin of apatient or otherwise that benefit from reduced pressure treatment. Awound is thus broadly defined as any damaged region of tissue wherefluid may or may not be produced. Examples of such wounds include, butare not limited to, abdominal wounds or other large or incisionalwounds, either as a result of surgery, trauma, sterniotomies,fasciotomies, or other conditions, dehisced wounds, acute wounds,chronic wounds, subacute and dehisced wounds, traumatic wounds, flapsand skin grafts, lacerations, abrasions, contusions, burns, diabeticulcers, pressure ulcers, stoma, surgical wounds, trauma and venousulcers or the like.

As is used herein, reduced or negative pressure levels, such as −X mmHg,represent pressure levels that are below standard atmospheric pressure,which corresponds to 760 mmHg (or 1 atm, 29.93 inHg, 101.325 kPa, 14.696psi, etc.). Accordingly, a negative pressure value of −X mmHg reflectsabsolute pressure that is X mmHg below 760 mmHg or, in other words, anabsolute pressure of (760−X) mmHg. In addition, negative pressure thatis “less” or “smaller” than X mmHg corresponds to pressure that iscloser to atmospheric pressure (e.g., −40 mmHg is less than −60 mmHg).Negative pressure that is “more” or “greater” than −X mmHg correspondsto pressure that is further from atmospheric pressure (e.g., −80 mmHg ismore than −60 mmHg).

The negative pressure range for some embodiments of the presentdisclosure can be approximately −80 mmHg, or between about −20 mmHg and−200 mmHg. Note that these pressures are relative to normal ambientatmospheric pressure. Thus, −200 mmHg would be about 560 mmHg inpractical terms. In some embodiments, the pressure range can be betweenabout −40 mmHg and −150 mmHg. Alternatively a pressure range of up to−75 mmHg, up to −80 mmHg or over −80 mmHg can be used. Also in otherembodiments a pressure range of below −75 mmHg can be used.Alternatively, a pressure range of over approximately −100 mmHg, or even−150 mmHg, can be supplied by the negative pressure apparatus. In someembodiments of wound closure devices described here, increased woundcontraction can lead to increased tissue expansion in the surroundingwound tissue. This effect may be increased by varying the force appliedto the tissue, for example by varying the negative pressure applied tothe wound over time, possibly in conjunction with increased tensileforces applied to the wound via embodiments of the wound closuredevices. In some embodiments, negative pressure may be varied over timefor example using a sinusoidal wave, square wave, and/or insynchronization with one or more patient physiological indices (e.g.,heartbeat). Examples of such applications where additional disclosurerelating to the preceding may be found include application Ser. No.11/919,355, titled “Wound treatment apparatus and method,” filed Oct.26, 2007, published as US 2009/0306609; and U.S. Pat. No. 7,753,894,titled “Wound cleansing apparatus with stress,” issued Jul. 13, 2010.Both applications are hereby incorporated by reference in theirentirety. Other applications that may contain teachings relevant for usewith the embodiments described herein may include application Ser. No.12/886,088, titled “Systems And Methods For Using Negative PressureWound Therapy To Manage Open Abdominal Wounds,” filed Sep. 20, 2010,published as US 2011/0213287; application Ser. No. 13/092,042, titled“Wound Dressing And Method Of Use,” filed Apr. 21, 2011, published as US2011/0282309; and application Ser. No. 13/365,615, titled “NegativePressure Wound Closure Device,” filed Feb. 3, 2012, published as US2012/0209227.

It will be understood that throughout this specification in someembodiments reference is made to an elongate, elongated or longitudinalstrip or strips. It is to be understood that these terms are to bebroadly construed and refer in some embodiments to an elongate materialhaving two parallel or substantially parallel faces, where incross-section a thickness of the material as measured perpendicular tothe faces is relatively smaller than a height of the material measuredparallel to the faces. While in some embodiments the strips may beconstructed from discrete lengths of material, in other embodiments thestrips may simply refer to elongate portions of an overall structurehaving two parallel or substantially parallel faces. The strips in someembodiments have a rectangular or generally rectangular-shaped faces,wherein a length of the face is longer than the height of the face. Insome embodiments, the length of the face may be more than 2 times, 4times, 6 times, 8 times or 10 times greater than the height of the face.

As used herein, the term “horizontal,” when referring to a wound,indicates a direction or plane generally parallel to the skinsurrounding the wound. The term “vertical,” when referring to a wound,generally refers to a direction extending perpendicular to thehorizontal plane. The term “longitudinal,” when referring to a wound,generally refers to a direction in the horizontal plane taken in adirection along which the wound is longest. The term “lateral,” whenreferring to a wound, generally refers to a direction in the horizontalplane perpendicular to the longitudinal direction. The terms“horizontal,” “vertical,” “longitudinal,” and “lateral” may also be usedto describe the stabilizing structures and wound closure devicesdescribed throughout this specification. When describing thesestructures or devices, these terms should not be construed to requirethat the structures or devices necessarily be placed into a wound in acertain orientation, though in certain embodiments, it may be preferableto do so.

FIG. 1 illustrates an embodiment of a negative pressure treatment system100 that comprises a wound packer 102 inserted into a wound 101. Thewound packer 102 may comprise porous materials such as foam, and in someembodiments may comprise one or more embodiments of wound closuredevices described in further detail herein. In some embodiments, theperimeter or top of any wound closure device inserted into the wound 101may also be covered with foam or other porous materials. A drape 104 maybe placed over the wound 101, and is preferably adhered or sealed to theskin on the periphery of the wound 101 so as to create a fluid-tightseal. An aperture 106 may be made through the drape 104—which can bemanually made or preformed into the drape 104—so as to provide a fluidicconnection from the wound 101 to a source of negative pressure such as apump 110. Preferably, the fluidic connection between the aperture 106and the pump 110 is made via a conduit 108. In some embodiments, theconduit 108 may comprise a RENASYS® Soft Port™, manufactured by Smith &Nephew. Of course, in some embodiments, the drape 104 may notnecessarily comprise an aperture 106, and the fluidic connection to thepump 110 may be made by placing the conduit 108 below the drape. In somewounds, particularly larger wounds, multiple conduits 108 may be used,fluidically connected via one or more apertures 106.

In some embodiments, the drape 104 may be provided with one or morecorrugations or folds. Preferably, the corrugations are aligned alongthe longitudinal axis of the wound, and as such may support closure ofthe wound by preferentially collapsing in a direction perpendicular tothe longitudinal axis of the wound. Such corrugations may aid in theapplication of contractile forces parallel to the wound surface and inthe direction of wound closure. Examples of such drapes may be found inapplication Ser. No. 12/922,118, titled “Vacuum Closure Device,” filedNov. 17, 2010 (published as US 2011/0054365), which is herebyincorporated by reference in its entirety.

In use, the wound 101 is prepared and cleaned. In some cases, such asabdominal wounds, a non- or minimally-adherent organ protection layer(not illustrated) may be applied over any exposed viscera. The woundpacker 102 is then inserted into the wound, and is covered with thedrape 104 so as to form a fluid-tight seal. A first end of the conduit108 is then placed in fluidic communication with the wound, for examplevia the aperture 106. The second end of the conduit 108 is connected tothe pump 110. The pump 110 may then be activated so as to supplynegative pressure to the wound 101 and evacuate wound exudate from thewound 101. As will be described in additional detail below and inrelation to the embodiments of the foregoing wound closure devices,negative pressure may also aid in promoting closure of the wound 101,for example by approximating opposing wound margins.

EXAMPLE 1

By means of a non-limiting example, an experiment was conducted todetermine the effectiveness of an embodiment of the wound closuredevices described above, with testing being performed on a cadavericmodel. A midline incision was made through the peritoneum and into theabdominal cavity of the cadaver, which was then filled with two salinebags with a total capacity of approximately 2 L so as to provide upwardtension to simulate the effects of abdominal edema and organ swellingthat may be seen, for example, in abdominal compartment syndrome. Thesebags, together with the intestines, were placed into the wound cavityunderneath an organ protection layer, as provided in the Renasys® A/Btreatment kit (Smith & Nephew).

With reference to FIG. 2A, a piece of black foam was inserted into theabdominal incision, sealed with a drape, and connected to a source ofnegative pressure via a fluidic connection (here, a Soft Port™ suctionport assembly manufactured by Smith & Nephew). FIG. 2B illustrates thearea of the wound after activation of the source of negative pressure.Negative pressure was then applied at 80, 120, and 180 mmHg. With allthree of these negative pressure levels, there was no significantdifference to the amount of wound margin contraction achieved, althoughvacuum levels below 80 mmHg did not appear to contract the wound marginsas much. This was true in all of the other subsequent experimentsdescribed herein.

Wound area measurements were taken before and after activation of thenegative pressure source. In this example, the size of the wound areabefore and after application of negative pressure decreased from 167 mm²to 126 mm². This is a difference of 25%.

Stabilizing Structures and Wound Closure Devices of FIGS. 3A-4E

FIGS. 3A-D illustrate different views of an embodiment of a woundclosure device comprising a stabilizing structure 1701. Here, thestabilizing structure 1701 comprises a first set of beams 1703 that arerigidly or semi-rigidly attached or bonded to a second set ofintersecting beams 1705. These beams 1703, 1705 form a planar supportstructure 1702 that is preferably substantially rigid within a plane.The beams 1703, 1705 may meet at right angles to each other (althoughother configurations, e.g., honeycombs are possible). Two or more planarsupport structures 1702 may be joined together to form the stabilizingstructure 1701, and each planar support structure 1702 is preferablyseparated from the other by spring elements 1711 and 1713, described infurther detail below. The number of planar support structures 1702 usedin the stabilizing structure may be tailored in relation to the size ofthe wound. For example, there may be 2, 3, 4, 5 or more planar supportstructures 1702 arranged parallel or substantially parallel to oneanother. The spring elements 1711, 1713 are preferably arranged so as toallow for compression of the stabilizing structure 1701 in one directionso as to bring the planar support structures 1702 closer together. In apreferred embodiment, the stabilizing structure 1701 may collapse to 40%or less of its original size, preferably 30% or less of its originalsize; more preferably, 20% or less of its original size; even morepreferably, 10% or less of its original size. In some embodiments, thestabilizing structure 1701 may collapse to 5% or less of its originalsize.

The spring elements 1711, 1713 are preferably resiliently flexible andbiased to be resiliently collapsible along a direction perpendicular tothe plane defined by the planar support structure 1702. In someembodiments, the elements 1711, 1713 may be inelastic, and retain theirshape when collapsed. In such embodiments, the spring elements or thestabilizing structure may be constructed with a ratchet mechanism thatmaintains the spring elements 1711, 1713 in their collapsedconfiguration.

In a preferred embodiment, these spring elements 1711, 1713 may be V- orU-shaped. Each spring element may comprise two elongate portions thatare bent relative to each other and form an obtuse angle (as shown inFIGS. 3A-3C), or an acute angle (as shown in FIG. 4A). Spring elements1711 preferably run in a plane parallel to beam 1705, and may beattached to either the beam 1703 or 1705. Similarly, spring elements1713 preferably run in a plane parallel to beam 1703, and may beattached to either the beam 1703 or 1705. For both spring elements 1711,1713, a preferred attachment point is at the junction between beams 1703and 1705. Preferably, the spring elements 1711 are arranged in a firstplurality of parallel planes, which run parallel to the direction of thebeam 1705, and the spring elements 1713 are arranged in a secondplurality of parallel planes which run parallel to the direction of thebeam 1703. The spring elements 1711 located between two adjacent planarsupport structures 1702 may be arranged in a repeating pattern withinthe first plurality of parallel planes. The spring elements 1713 locatedbetween two adjacent planar support structures 1702 may be arranged in arepeating pattern within the second plurality of parallel planes. In oneembodiment as illustrated in FIGS. 3A and 3C, adjacent spring elements1711 and 1713 form a diamond shape. However, different patterns,arrangements and numbers of spring elements may be employed. In someembodiments, the spring elements 1711, 1713 may have a spring constantranging between 10 and 30 N/m, more preferably between 15 and 25 N/m,and even more preferably 23 N/m. In some preferred embodiments, theforce required to compress seven spring elements by 15 mm equals 250 g.In some embodiments, the force required to compress the same sevensprings by the same distance ranges between 180 and 230 g. In someembodiments, there are a total of four spring elements 1711, 1713 per 10cm³. Of course, one will recognize that factors such as the springconstants and/or number of springs may be tailored to the particulartissue type and wound closure desired, and that higher or lower springconstants or numbers of springs may be used.

Standoffs 1707 and 1708 may be provided at the edges or along the outerfaces of the structure 1701, and which may be configured to contact thewound. In some embodiments, the standoffs 1707, 1708 may be extensionsof the beams 1703, 1705, or may be provided separately. In someembodiments, the standoffs 1707, 1708 may be provided with hook oranchor elements configured to anchor tissue placed into contact withthem. Additionally or alternatively, hook or anchor elements attached tothe structure 1701 may be provided separately from or instead of thestandoffs 1707, 1708. Such hook or anchor elements may be useful toenhance fascial tissue closure by ensuring that different tissue layers(e.g., muscle tissue, fat tissue) are closed at approximately the samerate. Preferably, the hook or anchor elements are configured so as to behave a release force (once engaged into tissue) that causes no orminimal pain to the patient while permitting sufficient pulling force tobe applied thereto so as to allow for wound closure. In someembodiments, different anchor elements may be used to engage differenttypes of tissue. For example, the release force to release an anchorelement from subcutaneous fatty tissue may be lower than the forceneeded to release another anchor element from muscle tissue.

Further, the anchor elements, by virtue of their attachment to thesurrounding tissue, may be useful in helping prevent a drape or othermaterials placed over the wound from going into the edges between theskin and the structure 1701. In some embodiments, the anchor elementsmay be broken off, which may aid in sizing the device as described belowso as to fit into a wound. Additionally, all or part of the structure1701 may be covered or embedded within a porous wound filler material.In such configurations, the standoffs 1707, 1708 may be used to provideadditional securement to any such wound filler material.

In use, the stabilizing structure 1701 may be cut to size as appropriateto fit the wound. Optionally, a porous material such as foam may beplaced around the perimeter of the structure 1701, and may be securedusing one or more of the standoffs 1707, 1708. The porous material mayalso surround or envelop the entire device, for example by using a foamenclosure. Foam may also be added into the entire structure 1701,including its interior portions, and if this is done duringmanufacturing, the structure 1701 is preferably capable of withstandinga reticulation process. Such a device comprising foam will havecomposite tensile structures that are to be considered when insertingthe device into the wound. When inserting the device into the wound, thestabilizing structure 1701 is preferably oriented such that the planarsupport structures 1702 are aligned such that they are perpendicular orsubstantially perpendicular to the general direction of wound closure,or perpendicular substantially perpendicular to the patient's skin.Optionally, an organ protection layer, which may comprise a polymersheet or other flexible material, optionally provided with apertures,may be placed into contact with at least the bottom portion of thewound. A drape may be sealed over the skin surrounding the wound, and asource of negative pressure may be placed into fluid communication withthe wound so as to effectuate wound closure. Further details regardingthe drape, the application of negative pressure, and other apparatusesand methods that may be used with these stabilizing structures, aredescribed below with respect to other embodiments.

FIGS. 4A-E illustrate different views and photographs of embodiments ofa wound closure device comprising a stabilizing structure 1201. Thisembodiment is similar in some respects and in function to the embodimentdescribed above in relation to FIGS. 3A-D, and share similar elements.The device comprises beams 1203 and 1205 that form a planar supportstructure 1202 separated by spring elements 1211 and 1213. Standoffs1207 and 1208 may also be provided. Here, however, the spring elements1211 and 1213 are thicker and have portions that are bent relative toeach other at acute angles. Additionally, compared to FIGS. 3A-D, thestructure 1201 has a greater volume and greater number of springelements 1211, 1213. As illustrated best in FIG. 4D, the spring elements1211 form a repeating diamond pattern within a first plurality ofparallel planes, with the diamond location being staggered betweenadjacent parallel planes. A corresponding pattern is employed for springelements 1213 with a second plurality of parallel planes. A similarconfiguration may be seen in FIGS. 3A-3D.

EXAMPLE 2

By means of a non-limiting example, an experiment was conducted todetermine the effectiveness of an embodiment of the wound closuredevices described above, with testing being performed on a cadavericmodel. FIGS. 5A-B illustrate the results where a structure with foam,similar to the embodiments of FIGS. 4A-E, was placed into a wound. Theperimeter of the structure was wrapped in a layer of foam.

Wound area measurements before and after application of negativepressure indicated that the wound area decreased by 64%, from 152 mm² to55 mm².

EXAMPLE 3

This non-limiting experiment tested a structure wrapped in foam andprestretched along its width and held in place by bendable plasticstrips, but otherwise similar to the embodiments of FIGS. 4A-E. FIGS.6A-B illustrate the wound size before and after application of negativepressure. Here, the wound area measured 154 mm² before the applicationof negative pressure, and 101mm² afterwards, for a 34% reduction inwound area.

EXAMPLE 4

FIGS. 7A-B illustrate the non-limiting results of an experiment where astructure similar to the embodiment of FIGS. 4A-E was placed into awound without any foam wrapping. The experiment was performed similarlyto the other examples described herein, and here, the wound areameasured 126 mm² before application of negative pressure, and 53 mm²afterwards, for a 58% reduction in wound area.

Stabilizing Structures and Wound Closure Devices of FIGS. 8A-16B, 19-20Band 32

FIGS. 8A-E illustrate additional embodiments of a wound closure devicecomprising a stabilizing structure 1100. FIG. 2A shows a perspectiveview of an embodiment of a stabilizing structure 1100. Here, thestabilizing structure 1100 is preferably comprised of two or moreinterlocking strips (described below in more detail with relation toFIG. 8B) that extend in directions approximately perpendicular to eachother when in a substantially uncollapsed configuration. The stabilizingstructure is preferably configured to collapse in one direction or alonga first plane while remaining relatively rigid and collapse-resistant ina direction perpendicular to the first direction or plane.

FIG. 8B illustrates side views of a bottom strip 1102 and a top strip1104 that may be used to make a stabilizing structure 1100 such as theembodiment illustrated in FIG. 8A. Each of the top and bottom strips1102, 1104 are preferably configured to movably interlock with eachother, for example via matching notches 1106 and 1108. One or morenotches 1106 may be provided on a top side of bottom strip 1102, andsimilarly, one or more notches 1108 may be provided on a bottom side oftop strip 1104. When assembled together, the one or more top and bottomstrips 1102, 1104 may be positioned so that the notches 1106, 1108 lineup. Preferably, the top and bottom strips 1102, 1104 are positioned atsubstantially perpendicular angles to each other, thereby permitting thenotches 1106, 1108 to slot together so as to create a movablyinterlocking structure. Typically, the number of notches 1106 on thebottom strip 1102 will equal the number of top strips 1108 that willform the stabilizing structure 1100, and vice versa. The notches 1106,1108 are preferably shaped with a width that permits the strips 1102,1104 to move from approximately perpendicular angles to angles far fromperpendicular (i.e., close to parallel) to each other, thus permittingthe stabilizing structure 1100 to articulate and collapse along onedirection or plane.

In a preferred embodiment, the strips 1102, 1104 are constructed from arigid or semi-rigid material, such as a polymer. Examples of suitablepolymers include polyethylene, polypropylene, polyurethane, polyvinylchloride, polystyrene, polyacrylate, polymethyl methacrylate, PEEK,silicone, polycarbonate, composites and laminates, or combinationsthereof. In some embodiments, the material may include compressed or“felted” reticulated foam. Of course, other materials, such as cardboardor metal may be used. Preferably, the materials may be at leastpartially porous so as to permit fluid to flow through the material.Further, such properties may aid in distributing negative pressurethrough the device and to the wound, and may aid in removing fluid fromthe wound dressing. Such materials may include, for example, low densitypolypropylene, foamed material, or sintered material. The material useddoes not necessarily need to be strong along the length of the strips1102, 1104, but should preferably be able to withstand pressure appliedto a top or bottom edge. Preferably, the material is capable ofwithstanding the pressure from atmospheric pressure exerted on a drapewhen up to 200 mmHg negative pressure is applied to the wound. In someembodiments, the material can withstand a force of 5 psi applied to atop or bottom edge.

In a preferred embodiment, each strip 1102, 1104 measures 180 mm long by30 mm high. The thickness of the strips 1102, 1104 may range, forexample, between 1.50 to 2.40 mm, although the thickness will beselected at least partly based on the ability of the material towithstand pressure being applied along its edge. The thickness ispreferably balanced between keeping the material thin enough to minimizethe compressed thickness of the stabilizing structure 1000, whilekeeping the material thick enough to avoid causing excessive localizedpressure upon the wound bed. The notches 1106, 1108 may measureapproximately 15 mm in height, and may be spaced apart from othernotches by 18 mm. Although the notches 1106, 1108 are shown with roundedbottoms, these may also be cut with squared-off or triangular bottoms.In some embodiments, the rounded edges reduce stresses onto the strips1102, 1104 so as to prevent fracture and crack propagation, and may alsoincrease the springiness of the stabilizing structure 1100.

It will be understood that the interlocking strips 1102, 1104 may notnecessarily need to be joined together via notches. Hinges or otherdevices could be used to provide the articulation or movableinterlocking ability illustrated above. In some embodiments, hinges maybe constructed from thinner areas of the same material used to constructthe strips 1102, 1104, and are configured to flex or bend to apredetermined position. The stabilizing structure 1100 could also bemolded as a single piece such that the interlocking strips 1102, 1104form a single unit.

Returning to FIG. 8A, the perspective view illustrates an example of astabilizing structure 1100 configuration with multiple interlocking topand bottom strips 1102, 1104 movably interlocked via multiple notches1106, 1108. The intersections of two top strips 1102 and two bottomstrips 1104 form a quadrilateral-shaped boundary space 1109. When thetop and bottom strips 1102, 1104 are at perpendicular angles to eachother, the space 1109 will be square or rectangular. However, as thestabilizing structure 1100 collapses along a direction or plane, thespace 1109 will become more diamond- or parallelogram-shaped. Thestabilizing structure 1100 will preferably comprise multiple spaces1109, which form cells defined by the walls of the top and bottom stripsand with openings on top and bottom ends.

FIG. 8C illustrates a top view of an embodiment of the stabilizingstructure 1100 where a porous wound filler material 1110 has been placedinto the quadrilateral-shaped boundary space 1109. Here, the porouswound filler material 1110 used is preferably soft and conformable so asto be able to adapt to the any change in the configuration of thestabilizing structure 1100 if it collapses. Preferably, the porous woundfiller material is a foam, such as a polyurethane foam. This porouswound filler material may be cast around the stabilizing structure 1100so as to completely encapsulate it. When used, the resulting stabilizingstructure 1100 may be cut to size so as to fit into a wound. Such porouswound filler material 1110 may be used to aid in the fluid transmissionor wicking of fluid from within a wound, and may also, when in contactwith the wound (e.g., when used in negative pressure wound therapy), aidin the healing of the wound.

FIG. 8D illustrates a perspective photograph of an embodiment of thestabilizing structure 1100 with a porous wound filler material 1110inserted into the spaces 1109. In some embodiments, additional porouswound filler material may also be used to encapsulate or surround thestructure 1100. For example, a sock or wrap may be fitted around thestructure 1100, and may for example be constructed from foam or gauze.When inserted into a wound, the stabilizing structure 1100 may bepreferably oriented so as to collapse in a direction generally parallelwith the orientation of collagen and other fibrous tissue fibers in thebody. This orientation is sometimes referred to as Langer's lines orKraissl's lines, and closing a wound in a direction coinciding with (andpreferably parallel to) these lines may heal faster and more easily thanattempting to close a wound in a direction perpendicular or opposed tothese lines. It will be appreciated that the other embodiments ofstabilizing structures described in this specification may also beoriented in the same manner with respect to Langer's lines or Kraissl'slines, or other landmarks.

In use, the stabilizing structure 1100 may be placed into a wound suchthat the upward facing portion of the structure 1100 is substantiallyrigid and resists collapse in the vertical direction once negativepressure is applied to the wound (e.g., once covered by a drape asdescribed previously). A porous material such as foam may be placedaround, into, and/or so as to surround or encapsulate the stabilizingstructure 1100. In some embodiments, an organ protection layer asdescribed previously may be placed into contact with at least the bottomportion of the wound. As negative pressure is applied, the structure1100 will then preferably collapse in the plane perpendicular to thevertical direction, aiding in wound closure. Due to the relativeincompressibility of the vertical dimension of the device, the pressureon the drape transmitted from the greater atmospheric pressure onto thewound will reduce the pressure applied to the stabilizing structure 1100onto the wound margins in comparison to existing prior art devices (suchas those illustrated in FIGS. 2A-B). Optionally, in this and otherembodiments described herein, negative pressure may be applied so as toincrease transmission of negative pressure to the sides of the woundrather than the bottom portions thereof. This may be accomplished, forexample, by providing an organ protection layer that at least partiallyshields the bottom of the wound from negative pressure. In a preferredembodiment, the sides of the wound would be provided with at least 100mmHg, preferably 120 mmHg, 140 mmHg, 180 mmHg, or 200 mmHg, while thebottom of the wound would be provided with at most 120 mmHg, morepreferably 80 mmHg, 40 mmHg, 20 mmHg, or 10 mmHg.

FIG. 8E illustrates a CT image of an embodiment of a stabilizingstructure 1100 described in FIGS. 8A-D inserted into an abdominal wound.The tissue fascia layers are also visible, with a subcutaneous fat layer1190 above a layer of muscle tissue 1192. With the application ofnegative pressure (as illustrated), improved fascial reapproximation andwound closure may be observed. In particular, the muscle tissue layers1192 on opposite sides of the wound have been moved much closertogether, while remaining attached to the other fascial layers. Inmeasurements, the width of the wound along the view illustrated reducedfrom approximately 82 mm to 28 mm, a reduction of 65%.

FIGS. 9A-C illustrate an embodiment of a wound closure device comprisinga stabilizing structure 1100 similar to that described above in relationto FIGS. 8A-E. Here, the stabilizing structure 1100 is constructed frominterlocking strips constructed from felted foam. The physicalrelationship between and the mechanism for the interlocking top andbottom strips 1102 and 1104 are substantially similar to what wasdiscussed previously above, and will not be repeated here. Felted foam,however, is foam (e.g., polyurethane foam) that has been heated andcompressed. After this procedure, the foam will be stiffer and lesscompressible, while still remaining porous. Such a material may beadvantageously used in a stabilizing structure 1100 used for a woundclosure device, as the material may be compressible in a plane definedby the top and bottom strips 1102, 1104, as shown in FIG. 9B. However,the material is substantially rigid in the vertical direction, asillustrated in FIG. 9C, where a weight has been placed over the foamwithout substantial buckling. Here, the foam can support approximately 6kg of weight, and embodiments of the device have been measured tosupport at least 3 psi of applied pressure without collapse. Further,while such material is substantially rigid, the porous nature of thematerial permits negative pressure to be transmitted to the wound andfor wound exudate to be removed.

FIGS. 10A-B are photographs of further embodiments of wound closuredevices. FIG. 10A illustrates an embodiment of a wound closure device1301 that preferentially collapses along one direction. Here, the woundclosure device 1301 comprises a porous wound filler material (e.g.,foam) into which one or more slots 1303 have been cut. These slots 1303preferably extend longitudinally through the thickness of the woundclosure device 1301. Accordingly, the empty space will permit the woundclosure device to preferentially collapse in a direction when a force isapplied in a direction perpendicular to the slots 1303. Because theempty space is easier to compress than the remainder of the foam, thewidth and thickness of the foam will preferably not (or minimally)compress compared to the resulting compression perpendicular to thelength of the wound closure device 1301.

As illustrated in FIG. 10B, the wound closure device 1301 may also beprovided with holes or cells 1305 in other configurations, such asdiamond-shaped holes forming a lattice. This configuration permitscompression along the length and width of the wound closure device dueto the compressible holes 1305, while the comparatively more rigidthickness of the foam resists compression to a greater extent.

In some embodiments, stabilizing structures similar to those illustratedabove in FIGS. 8A-E may be constructed as a single unit, for example bymolding, rather than from multiple parts. As with thepreviously-described embodiments, the stabilizing structures areconfigured to form an array of one or more cells defined by one or morewalls and forming a plane, with each cell having a top and bottom endwith an opening extending through the top and bottom ends in a directionperpendicular to the plane. In some embodiments, the stabilizingstructures may have cells that are square, diamond, oblong, oval, and/orparallelepiped, and non-limiting examples of the same are illustrated inFIGS. 11-20 . While some embodiments may have cells that are all thesame shape, the cells may also be tailored to be larger, smaller, ordifferently-shaped than other cells in the structure. The shape and sizeof the cells may be tailored to the desired characteristics (e.g.,resilience and ease of collapse) for optimal wound closure and healing.

Construction of a single unit stabilizing structure may be advantageousin terms of ease of use and cost. For example, single unit stabilizingstructures may be trimmed as necessary to fit into a wound site. Thematerial used is preferably biocompatible, and even more preferablynonadherent to the wound site. Suitable materials are preferably chosento be soft while remaining sufficiently strong to resist collapse in avertical direction, and may include polymers, such as polyethylene,polypropylene, polyurethane, silicone (including siloxanes), ethyl vinylacetate, and copolymers and blends thereof. The hardness of the materialmay affect the thickness of the resulting stabilizing structure, and maybe selected based upon the desired thickness of the stabilizingstructure components (including hinges and other joints thereof) and theability of the stabilizing structure to resist collapse, e.g., due tothe atmospheric pressure acting upon a drape placed over the stabilizingstructure. Suitable durometer hardnesses of materials used range fromabout 30 shore to 120 shore (as measured on the Shore durometer type Ascale), preferably from about 40 shore to 60 shore, and even morepreferably about 42 shore. Generally, the material chosen is preferablysofter (while still satisfactorily meeting other material requirements),as harder materials may provide reduced levels of closure as thehardness increases.

FIG. 19 is a photograph of an embodiment of such device 1100 constructedas a single unit. The apertures 1109 are filled with a porous material1110, which in some embodiments may comprise foam. Here, the device 1100is inserted into a wound.

FIGS. 11A-B illustrate an embodiment of a stabilizing structure 1100configured to preferentially collapse in only one horizontal directionwhile remaining substantially rigid or uncollapsed when force is appliedin a vertical direction. Preferably, the stabilizing structure 1100 isconstructed as a single unit as illustrated so as to form one or morecells 1131. Here, two or more longitudinal strips 1120 (which form thewalls of the cells) may have relatively straight configurations, and areconnected together via one or more collapsible cross strips 1122. Itwill be appreciated that in a single unit embodiment, the strips aremerely portions of the same material that may have been formed togetherto form the entire single unit structure. The collapsible cross strips1122 may be angled or indented so as to make them more likely tocollapse in a direction generally parallel to their length. In thisembodiment illustrated herein, the collapsible cross strip 1122 is morelikely to collapse at the apex of the angled portion and at thejunctions to the longitudinal strips 1120 when a force is applied in adirection approximately parallel to the general length of thecollapsible cross strip 1122. In some embodiments, the collapsible crossstrip is configured to fold into a portion (which may be thinner) of thelongitudinal cross strip 1120.

In some configurations, one or both of the longitudinal strips 1120and/or collapsible cross strips 1122 may comprise one or more notchespositioned along a length thereof. These notches promote fluid transferacross the structure, and aid in distributing negative pressure. In someembodiments, notches may be used in conjunction with a porous materialso as to enhance fluid transfer. In relation to the longitudinal strips1120, the collapsible cross strips 1122 may be positioned alternatelyalong the length of the longitudinal strips 1120, as best illustrated inFIG. 11B, to form a configuration somewhat analogous to a “stretcherbond” used in bricklaying. Of course, other configurations are possible.Further, although this embodiment is illustrated as being formed as asingle unit, those of skill in the art will recognize that thisembodiment (and the others described below) may be constructed frommultiple pieces joined or connected together.

FIGS. 20A-B are photographs of an embodiment of a stabilizing structure1100 similar to the one described above in relation to FIGS. 11A-B.Here, the structure 1100 is inserted into a wound 1140 and placed undera drape 1145. A source of negative pressure is connected via a fluidicconnector 1150. FIG. 20B is a closeup view of the stabilizing structure1100 photographed in FIG. 20A, which illustrates how the cells 1131collapse upon the application of negative pressure while under the drape1148. An optional porous wound filler 1148 is also illustrated.

FIG. 12 illustrates another embodiment of a stabilizing structure 1100,here comprising two or more longitudinal strips 1120 attached to eachother via one or more angled cross strips 1124 so as to form cells 1131.As with the embodiment illustrated in the preceding figure, thestabilizing structure 1100 is configured to collapse when pushed in adirection perpendicular to the length of the longitudinal strips 1120,while remaining substantially rigid or uncollapsed when force is appliedin a vertical direction. The angled cross strips 1124 are preferablyattached to the longitudinal strips 1120 so as to form anon-perpendicular angle so as to promote collapse of the stabilizingstructure 1100 in the direction perpendicular to the length of thelongitudinal strips 1120. As with FIGS. 8A-B, one or more notches may beformed on either or both of the longitudinal strips 1120 and/or angledcross strips 1124.

FIG. 13 illustrates a single unit stabilizing structure 1100 comprisingone or more pairs of curved longitudinal strips 1126. Each individuallongitudinal strip 1126 may be formed as a “wavy” strip (when seen froma vertical orientation) that, when joined face-to-face, form a one ormore circular or ovoid cells 1127. As with the other stabilizingstructures illustrated herein, this structure 1100 is configured topreferably collapse along a horizontal plane or direction whileremaining substantially rigid or uncollapsed when force is applied in avertical direction. Although the structure 1100 is illustrated here asbeing formed from a single unit, the structure may be constructed fromtwo or more curved longitudinal strips 1126 welded or attached togetherat the points shown. As with several other embodiments described herein,one or more notches may be made onto the walls so as to aid in fluidtransfer across and through the structure 1100.

FIG. 14 illustrates a stabilizing structure 1100 similar to the oneillustrated in FIG. 13 . Here, however, zigzag longitudinal strips 1128are joined to form diamond-shaped (rather than circular or ovoid) cells1129. It will be of course appreciated that this embodiment may also bemanufactured using substantially straight strips in a style similar tothe embodiments illustrated in FIGS. 8A-D.

FIG. 15 illustrates a stabilizing structure 1100 comprising verticalsegments 1130 joined together at approximately perpendicular angles soas to form quadrilateral or square cells 1131. Preferably, the verticalsegments 1130 are of a square or rectangular shape, with tapers 1132that join the segments together in a movable and flexible configuration.As with the other embodiments described herein, this stabilizingstructure 1100 may be manufactured as a single unit, and is preferablyconfigured to collapse in a horizontal plane or direction whileremaining substantially uncollapsed in a vertical direction.

FIG. 16A-B illustrates another stabilizing structure 1100 similar to theembodiment illustrated above in FIG. 15 . The vertical segments 1130 arepreferably joined together so as to form one or more quadrilateral orsquare cells 1131. Here, however, the vertical segments 1130 do notcomprise a tapered portion 1132. However, one or more notches may bepresent on the underside (wound-facing side) of the structure 1100, andwhich function as described in preceding embodiments. Although thisembodiment may be manufactured from multiple vertical segments 1130, itis preferably molded as a single unit.

FIG. 16B illustrates a CT image of an embodiment of a stabilizingstructure 1100 as described above in relation to FIG. 16A, and which hasbeen inserted into an abdominal wound. Subcutaneous fat layers 1190 arebilateral and present over muscle tissue layer 1192. Upon application ofnegative pressure (as illustrated), improved fascial reapproximation andwound closure may be observed. Here, the width of the wound along theview illustrated reduced from approximately 82 mm to 52 mm, a reductionof 37%.

FIG. 32 illustrates an embodiment of a stabilizing structure similar tothe structures described in FIGS. 11-16A. In this embodiment, thelongitudinal strips and cross strips are formed from a single piece ofmaterial and form rows of flexible cells that are configured to collapsein a horizontal plane. Because each of the longitudinal and cross stripsare formed from the same flexible material, applying a lateral force tothe structure causes the cells to collapse generally independently ofeach other. In other words, the collapse of one or more cells in a rowdoes not necessarily cause the collapse of other cells in the same row.

EXAMPLE 5

In this next non-limiting experiment, the wound described in thepreceding examples had an embodiment of the stabilizing structure devicedescribed above in relation to FIGS. 8A-E inserted into the abdominalcavity. In this experiment, and as illustrated in FIG. 17A, white foaminserts were placed into the quadrilateral openings of the stabilizingstructure, and the outer edges (in contact with the wound) were wrappedin black foam. The wound and stabilizing structure were then sealed witha drape and connected to a source of negative pressure as describedpreviously.

Wound area measurements were taken before and after activation of thenegative pressure source. Here, the size of the wound before applicationof negative pressure was measured as 171 mm². Upon the application ofnegative pressure, as illustrated in FIG. 17B, the area of the wound wasgreatly reduced to 55 mm², a reduction of 68%. It is noted that here andin the following examples, as the wound area contracts along its width,the length of the wound increases slightly, indicating that the tissuemargins are returning to their original anatomical position.

EXAMPLE 6

FIGS. 18A-B illustrate the results of a non-limiting experiment similarto those illustrated above, where a stabilizing structure similar to theembodiments of FIGS. 8A-E was inserted into the abdominal cavity. Here,the spaces in the quadrilateral openings of the stabilizing structurewere empty, and a layer of foam was wrapped around the outer edges ofthe structure.

Wound area measurements before and after application of negativepressure indicated that the wound area decreased by 63%, from 155 mm² to58 mm².

Without wishing to be bound by theory, the greater reduction in woundarea in the preceding examples, as compared to the black foam control ofExample 1, is believed to be due to the fact that the wound devices usedtherein do not significantly compress in a vertical direction whennegative pressure is applied. This is different from traditional foamdressings, where the application of negative pressure causes downwardpressure on the foam due to the air pressure pressing onto the drape,which is then transmitted along the foam dressing into a horizontalforce that pushes the wound margins outward. With the use of astabilizing structure as used in the various examples illustrated here,the foam and other dressing components are not pushed outward, and thusthe wound margins may be approximated more easily so as to achievefaster wound closure. In fact, in some experiments, certain embodimentsof the wound devices projected upward over the wound margins, and thesevertical surfaces may therefore allow for atmospheric pressure toproduce contractile forces onto the devices and/or the wound margins.

Traditional negative pressure wound treatment typically uses foam (orother porous materials) placed into a wound underneath a drape, to whichnegative pressure is applied to the wound. In such situations, theapplication of negative pressure may cause downward pressure on the foamdue to the air pressure pressing onto the drape, which is thentransmitted along the foam dressing into a horizontal force that pushesthe wound margins outward. Without wishing to be bound by theory, it isbelieved that some of the embodiments of stabilizing structures, woundclosure devices, and wound treatment devices, methods, and systemsdescribed below are able to cause a greater reduction in wound area ascompared to traditional negative pressure treatment. One of thesefactors is believed to be because embodiments of the stabilizingstructures and wound closure devices described herein do notsignificantly compress in a vertical direction when negative pressure isapplied. With the use of certain embodiments described herein, foam andother dressing components are not pushed outward due to negativepressure, and thus the wound margins may be approximated more easily soas to achieve faster wound closure and better wound healing.

Stabilizing Structures and Wound Closure Devices of FIGS. 21A-27B

FIG. 21A is a photograph of an embodiment of a wound closure devicecomprising a stabilizing structure 2100 that may be placed or insertedinto a wound. Here, the device comprises a plurality of cells 2102provided side-by-side in a generally planar configuration. Preferably,the stabilizing structure 2100 is configured to collapse in a directionalong a plane 2101 defined by the width of the device, withoutsignificantly collapsing in a direction perpendicular to the plane 2101.That is, when viewed in the figure, the stabilizing structure 2100 willcollapse in the horizontal direction, but will not compress in thevertical direction. In some embodiments, the stabilizing structurecollapses in conjunction with the movement of tissue. Here, the cells2102 are preferably open at both ends in a direction perpendicular tothe plane 2101.

Each of the cells 2102 is preferably formed with four walls 2104, eachwall 2104 being joined to the next by a flexible joint 2106. The joints2106 are preferably designed so as to be more flexible than the walls2104, and promote collapse of the stabilizing structure 2100 in thedirection of the plane. Of course, it will be understood that otherconfigurations are possible, and in some embodiments each cell 2102 maybe defined by less than or greater than four walls 2104, for examplefive walls or six walls, thus forming pentagonal or hexagonal cells. Thecells 2102 may not necessarily be symmetric, and can form rectangular,diamond, rhomboidal, trapezoidal, parallelepiped, oblong, oval, andother such shapes in addition to the square-walled embodimentillustrated herein.

One or more of the walls 2104 defining the one or more cells 2102 mayfurther comprise an insert 2115 disposed therein, and described ingreater detail below in FIGS. 22A-F. Preferably, the insert 2115 will beconstructed from a material more rigid than the material used toconstruct the remainder of the wall 2104. Some suitable materials mayinclude metals such as titanium, stainless steel, and largely inertalloys (such as monel and hastelloy), and/or polymers such aspolyurethane, silicone, rubber, isoprene, polyethylene, polypropylene,nylon, polyacrylate, polycarbonate, and PEEK. Some embodiments may alsocomprise composite materials, including resin-reinforced fibercomposites where the resin may be, for example, various types ofepoxies. Suitable fibers may include glass, carbon, carbon nanotubes,grapheme, and aramids (e.g., Kevlar). Preferably, the material chosenfor the insert 2115 is not only sufficiently rigid, but also able toadhere to the material used in the wall 2104. For example, the insertmaterial is preferably able to adhere to softer polymers such assilicones used in the wall 2104. The more rigid materials used in theinsert 2115 may provide for additional collapse resistance in thedirection perpendicular to the plane for the stabilizing structure 2100.

In some embodiments, one or more notches 2109 may be provided betweenmultiple walls 2104, and which may further aid in permitting theflexible joints 2106 to move. Without wishing to be bound by theory, thenotches 2109 may also aid in distributing negative pressure andtransmitting fluid throughout the stabilizing structure 2100 whennegative pressure is applied, for example in a clinical care setting.Some embodiments may also comprises holes in the walls 2104 or joints2106, or be constructed from porous materials.

Preferably, a cavity 2108 is provided within each wall 2104 for theinsert 2110 to be disposed therein. The walls 2104 may be molded aroundeach insert 2115. An insert 2115 may also be inserted into the cavity2108 after the wall 2104 is manufactured. While the embodimentillustrated here and in the subsequent images shows a single insert 2115in each wall 2104, some embodiments may be provided with one or moreinserts 2115 disposed therein.

FIG. 21B illustrates an embodiment of a stabilizing structure 2100 withmany similar features to FIG. 21A. Here, an insert 2111 comprisesstructural differences compared to the insert 2110, and is discussed inmore detail below in relation to FIG. 22E. When inserted or placedwithin the cavity 2108, one or more of the walls 2104 may comprise ahole 2105 communicating through at least one aperture in the insert2111. In addition to any notches 2109, the one or more holes 2105 maypermit additional displacement of wound exudate and distribution ofnegative pressure within the stabilizing structure 2100.

FIG. 21C illustrates an embodiment of a stabilizing structure 2100 withsimilar features as the other embodiments described previously. In thisembodiment, the stabilizing structure 2100 comprises an insert 2112described in greater detail below in FIG. 22F.

Similarly, FIG. 21D illustrates an embodiment of a stabilizing structure2100 comprising an insert 2113 described in greater detail below in FIG.22D. FIG. 21E illustrates an embodiment of a stabilizing structure 2100comprising an insert 2114 described in greater detail in relation toFIG. 22A.

In the preceding embodiments of stabilizing structures 2100 comprisingvarious inserts 2110, 2111, 2112, 2113, and 2114, it will of course beunderstood that embodiments of the stabilizing structure 2100 does notneed to contain only one type of insert. Likewise, each cell 2102 orwall 2104 may comprise one or more different types of inserts, or noinserts at all. Varying the different inserts and other properties ofthe cells 2102 and walls 2104 may thus permit the stabilizing structure2100 to be tailored to the appropriate wound type so as to effectoptimal wound closure and/or treatment.

FIGS. 22A-F illustrate examples of different inserts that may be used aspart of a stabilizing structure 2100. Preferably, these inserts may beplaced, molded into, or formed as part of a wall 2104 in a stabilizingstructure 2100 (e.g., of the types illustrated above in FIG. 21A-E).Various modifications may be made, as described below, that may improveor alter characteristics of the inserts.

Turning now to FIG. 22A, the embodiment of the insert 2114 illustratedhere is approximately rectangular in shape, and is adapted to beinserted or formed into one or more of the walls 2104 of an embodimentof the stabilizing structure 2100. In some embodiments, one or more ofthe inserts 2114 may have a height greater than the width, and the wall2104 may have a height between 20 mm and 30 mm, preferably 25 mm, and awidth between 8 mm and 14 mm, preferably 10.8 mm. The insert 2114 ispreferably thin but with enough structural strength to resist collapse,and in some embodiments, measuring between 0.5 mm and 4 mm in thickness,preferably 1-2 mm. These measurements may be appropriate for the otherinserts discussed below as well.

FIG. 22B illustrates an embodiment of the insert 2110 with a generallyrectangular configuration, but provided with two notches 2201 cutdiagonally across a top end of the insert 2100. The notches 2201 mayfacilitate clearance of the insert 2100 from any notches 2109 that maybe provided in the walls 2104. Further, the notches 2201 may also aid inthe insertion of the insert 2100 into the cavity 2108 of the wall 2104.The notches 2201 may also be helpful in conjunction with the notches2109 in further defining a channel or other opening for fluid to betransmitted or transferred between and through each cell 2102. Thenotches 2201 may also aid in ensuring that the entire stabilizingstructure is able to more easily collapse.

FIG. 22C illustrates an embodiment of an insert 2115 provided with twonotches 2201 as well as a horizontal lip 2203. The horizontal lip 2203may aid in inserting the insert 2115 into the cavity 2108 of the wall2104, or may aid in fixing the wall 2104 around the insert 2115 when thewall is molded around it. The horizontal lip 2203 may be beneficial ineffectively reducing the bulk of the insert at one end of the wall 2104,and in conjunction with a softer material used in the wall 2104, maythereby increase comfort due to the correspondingly greater amount ofwall material. In some embodiments, the horizontal lip 2203 and/ornotches 2201 may be present on both ends of the insert 2115 or otherinserts described herein. In some embodiments, the horizontal lip 2203is approximately half the thickness of the overall insert 2115. Forexample, the insert 2115 may be between 0.5 mm and 4 mm in thickness,preferably 2 mm. If the insert 2115 measures 2 mm in thickness, thethickness of horizontal lip 2203 may be 1 mm.

FIG. 22D illustrates an embodiment of the insert 2113, and which issimilar to the embodiment used in the stabilizing structure 2100illustrated in FIG. 21D. This insert 2113 may comprise one or moreapertures 2205, which in some embodiments may communicate with one ormore holes 2105 that may be formed through one or more walls 2104. Insome embodiments, the apertures 2205 are arranged in a 2×3 patternillustrated here, although other arrangements are possible. Notches 2201may also be present.

FIG. 22E illustrates an embodiment of the insert 2111, which is similarto the embodiment used in the stabilizing structure 2100 illustrated inFIG. 21B. The insert 2111 preferably comprises two notches 2201. Ahorizontal lip 2203 may also be provided. Preferably, one or moreapertures 2205 may be formed therein. In some embodiments, one or moreof the apertures 2205 may extend to the edge of the insert 2111 asillustrated. In some embodiments, the apertures 2205 may be configuredto have four apertures arranged around a central aperture, althoughother configurations are of course possible. In some embodiments, thereduced amount of insert material at the locations of the apertures maybe advantageous to provide a greater amount of softer wall material at ahinge point, where this may consequently increase flexibility. In apreferred embodiment, the insert 2111 has a height of 25 mm and a widthof 10.8 mm, with a thickness of 2 mm. The first set of apertures may becentered approximately 5 mm from the bottom edge of the insert 2111, thecentral aperture may then be centered approximately 11 mm from thebottom, and the top set of apertures may be centered 17 mm from thebottom.

FIG. 22F illustrates an embodiment of the insert 2112, which shares somesimilarities to the embodiment used in the stabilizing structure 2100illustrated above in FIG. 21C. The insert 2112 preferably may compriseone or more channels 2207 formed therein. Preferably, the one or morechannels 2207 are disposed in a horizontal configuration across thewidth of the insert 2112. While the insert 2112 is preferablyconfigured, like several other embodiments described herein, to remainsubstantially uncompressed in the vertical direction, the inclusion ofone or more horizontal channels 2207 may aid in providing additionalrigidity in the direction of the plane defined by the cells 2102. Insuch a case, the rigidity of the one or more walls 2104 may be enhanced,and may thus control the compression of the stabilizing structure 2100such that any collapse or bending occurs substantially only at the oneor more joints 2106.

FIGS. 23A-F illustrate an embodiment of a stabilizing structure 3001configured to be inserted into a wound. The stabilizing structure 3001preferably comprises at least one top strip 3002 extending in a firstdirection (e.g., along an x axis) and at least one bottom strip 3004extending in a second direction (e.g., along a y axis perpendicular tothe x axis), these being preferably arranged into an array comprisingmultiple strips 3002, 3004. The strips 3002, 3004 are preferablyconnected together in a movably interlocking configuration, whichpreferably comprises an interlock mechanism 3006. The strips 3002, 3004are preferably arranged in an un-collapsed configuration wherein thestrips 3002 and 3004 are disposed at angles approximately perpendicularto each other. This arrangement forms a first plane that the stabilizingstructure 3001 preferably adopts. Preferably, the stabilizing structure3001 is more rigid in the direction perpendicular to the plane (i.e., inthe vertical direction or along a z axis), and thereby substantiallyresists compression or deformation in that direction.

To aid in the closure of a wound, the stabilizing structure 3001 ispreferably movable from the substantially un-collapsed configuration toa collapsed configuration, as illustrated in FIG. 23F. This may bebeneficial for wound closure and healing, as described previously. Inuse, negative pressure may apply a closing force across the margins ofthe wound that the stabilizing structure 3001 is inserted into. As thestructure 3001 is preferably configured to be substantially rigid in thevertical direction (i.e., perpendicular to the plane defined by thestructure 3001), pressure resulting from atmospheric pressure exertedonto the structure 3001 via the drape is focused substantially downwardrather than outward, such that the wound margins are no longer pushedoutward as in conventional negative pressure dressings.

Preferably, the structure 3001 adopts a smaller area in the first planeas a result of moving to the compressed configuration. As such, thestructure 3001 aids in wound closure by aiding re-approximation of thewound margins. In some embodiments, the stabilizing structures describedherein are able to reduce their captured volume when in a collapsedconfiguration (i.e., the volume change between an uncompressed andcompressed stabilizing structure) by at least 10%, preferably at least15%, and even more preferably at least 25%.

FIGS. 23C-E illustrate close-ups of the interlock mechanism 3006. It isto be noted that although reference may be made to various parts of theinterlock mechanism 3006 being present on either the top strip 3002 orbottom strip 3004, this description should not be considered as limitingin terms of orientation, and the same interlock mechanism 3006 may beconstructed with the top or bottom strips 3002, 3004 reversed.

In a preferred embodiment, the interlock mechanism 3006 preferablycomprises two clasps 3010 extending downward from the top strip 3002.Preferably, the clasps 3010 are parallel to each other so as to be onopposite sides of a projection 3012 extending upward from the bottomstrip 3004. The clasps 3010 preferably comprise a lip or hook 3011 thatmay secure themselves under an end 3013 located at the distal end of theprojection 3012. In a preferred configuration, the enlarged end 3013 isarranged such that all or a portion of the lip 3011 engages with theenlarged end 3013. The combination of the lip 3011 and enlarged end 3012may aid in preventing the top strip 3002 from disengaging in a verticaldirection away from the bottom strip 3004. In some embodiments, theprojection 3012 may abut on the bottom edge of the top strip 3002. Insome embodiments, however, and as illustrated here, a stabilizing post3014 may be present to locate the distal side of the projection 3012 andenlarged end 3013.

FIGS. 24A-D illustrate an embodiment of a stabilizing structure 3201assembled in a similar manner to the embodiment illustrated above inFIGS. 23A-F. Here, the interlock mechanism 3006 comprises four clasps3010 surrounding the projection 3012 and the enlarged end 3013 of theprojection 3012. Preferably, the clasps 3010 are arranged in a mutuallyorthogonal configuration, although different orientations arecontemplated as well. It will be understood that any number of clasps3010 may be used to secure the projection 3012, for example three orfive clasps 3010.

It will be noted that due to the addition of additional clasps 3010 incomparison to the embodiment illustrated in FIGS. 23A-F, the embodimentillustrated here will have a compressed configuration that is slightlylarger, as illustrated in FIG. 24D. This may be useful in somesituations; for example, some wounds may require a more gradual closureof the wound margins, and the embodiment described here may be welladapted for this purpose. For example, in clinical situations involvingcompartment syndrome, especially in the abdomen, application of fullwound closure may not be appropriate or desirable, as wound closure maycause complications such as excessive pressure on organs and underlyingtissue structures and/or reduction of blood flow to distal anatomicalstructures. Additionally, in some cases a too rapid or complete woundclosure may be too painful for a patient. Accordingly, limiting theamount of closure may therefore be beneficial in such types of wounds.

FIGS. 25A-E illustrate an embodiment of a stabilizing structure 3301comprising an interlock mechanism 3006 arranged in a tubularconformation. In this embodiment, a cup-shaped member 3020 is preferablyconfigured to receive the enlarged end 3013 of the projection 3012. Theprojection 3012 may extend vertically from the top strip 3002. Thecup-shaped member 3020 is preferably cylindrical or tubular in shape,and may extend vertically from the bottom strip 3004, although it willbe understood that the cup-shaped member 3020 and projection 3012 may belocated on opposite strips.

Preferably, one or more slits 3021 are formed into the cup-shaped member3020 so as to permit some “give” to permit the projection 3012 to bereceived into the cup-shaped member. A lip or hook 3022 may also aid insecuring the enlarged end 3013 of the projection 3012. A stabilizingpost 3014 may also be present to prevent the projection 3012 fromextending too deeply into the cup-shaped member 3020.

FIG. 25E illustrates a compressed view of an embodiment of thestabilizing structure 3301. Compared to FIG. 23F, this embodiment has aslightly larger compressed configuration.

FIG. 26 schematically illustrates an embodiment of a stabilizingstructure 3400 configured to be inserted into a wound. Here, thestabilizing structure 3400 is shown inserted into a wound 3405.Preferably, the stabilizing structure 3400 preferably comprises at leastone, and more preferably at least two, long strips 3402 whoselongitudinal length may be oriented along a longitudinal axis of thewound 3405, or along a direction along which closure is sought. Each ofthe one or more long strips 3402 are preferably substantially rigid andextend substantially along the entire length of the wound 3405. In apreferred embodiment, the long strip 3402 is continuous and does nothave any breaks or hinges along its length. This is in contrast tocertain other embodiments described above.

One or more struts 3404 are preferably attached at one or more points tothe long strip 3402. Preferably, these struts 3404 are movably attached,for example via a hinge-like attachment or flexible joint, such thatthese may collapse in a direction perpendicular to a longitudinal lengthdefined by the length of the one or more long strips 3402. In someembodiments, the struts 3404 may be angled at a non-perpendicular anglewith respect to the long strip 3402 so as to collapse more readily. Inembodiments comprising two or more long strips 3402, the struts 3404 maybe hinged between two parallel long strips 3402.

It will be recognized that while these struts 3404 may be configured tocollapse along a direction perpendicular to the longitudinal length ofthe one or more long strips 3402, the struts 3404 are preferably rigidin a vertical direction (i.e., in the direction extending upward from aplane defined by the wound 3405). As such, a combination of the struts3404 and the long strips 3402 may thus form a stabilizing structure 3400that is substantially rigid in a vertical direction while beingcollapsible in a horizontal direction perpendicular to the longitudinalaxis of the long strips 3402 (i.e., in the plane of the wound 3405).

FIG. 27A illustrates a top view of an embodiment of stabilizingstructure 3400 cut into an oval shape and inserted into a wound 3405.Preferably, the stabilizing structure 3400 comprises a plurality ofelongate strips 3402 whose longitudinal length may be oriented along alongitudinal axis of the wound 3405, or along a direction along whichclosure is sought. Each of the plurality of elongate strips 3402 ispreferably substantially rigid and extends substantially along theentire length of the wound 3405. A plurality of intervening members arepositioned between adjacent elongate strips 3402. These interveningmembers may be struts 3404 as described with respect to FIG. 26 ,preferably attached at one or more points to the elongate strips 3402.The intervening members may also be portions of elongate strips such asdescribed with respect to FIGS. 23A-25E above, extending perpendicularor at an angle to elongate strips 3402. The stabilizing structure ofFIG. 27A may also comprise the embodiments described with respect toFIGS. 21A-22F.

FIG. 27B illustrates a top view of an embodiment of an oval shapedstabilizing structure 3400 inserted into a wound 3405. This embodimentmay have the same configuration as described above with respect to FIG.27A. Additionally, foam 3406 can be inserted between and around thestabilizing structure.

Stabilizing Structures and Wound Closure Devices of FIGS. 28A-31 and33-35

FIG. 28A illustrates an embodiment of a method for the closure of awound using any of the stabilizing structures described hereinbefore oras hereafter described, through the application of tension along an axisof wound 3405. In this example, when the wound is viewed from above,tension is applied along the longitundinal axis of the wound, generallyrepresented by line 3408. Tension along the longitundinal axis preventscontraction of the wound along the longitudinal axis, however thetension along the longitudinal axis can cause the lateral edges of thewound to be drawn together, promoting wound closure. In someembodiments, additional inward tension can be applied to the lateraledges of the wound, thereby providing additional wound closing force.

FIG. 28B illustrates an embodiment of a method for the closure of awound through the use of a stabilizing structure 3400 that collapses andlengthens when a wound is treated under negative pressure. Asillustrated, the stabilizing structure 3400 may be cut to an appropriatesize to approximate the shape of the wound (e.g., in an oval shape), andthe stabilizing structure is placed in the wound 3405. In someembodiments as described above, the stabilizing structure may have aplurality of diamond-shaped cells, and the cells are arranged in thewound in an orientation that causes the cells to be flattened as thelateral edges of the wound come closer together, while becoming longeralong the longitudinal axis of the wound. It will be recognized thatwhile this structure is configured to collapse under negative pressurehorizontally within the wound in a direction perpendicular to thelongitudinal axis of the wound, the structure is substantially rigid inthe vertical direction. Line 3408 represents the length of the structureprior to lengthening under negative pressure, while line 3410 representsthe final length of the structure after collapsing and lengthening undernegative pressure. Lines 3412 and 3414 represent the lengths ofparticular sections within the stabilizing structure. In certainembodiments, when is wound is treated with application of negativepressure, the structure will collapse inward on one axis, therebylengthening the structure by some additional amount in another axis thatcan be the sum of the lengths of lines 3412 and 3414. In someembodiments, the structure can lengthen by amounts other than the sum oflines 3410 and 3412.

In some embodiments, the collapse can occur slowly, thereby applyingincreasing longitudinal tension over a long period of time. In certainembodiments, the collapse and lengthening of the structure can occurimmediately upon application of negative pressure. In furtherembodiments, the collapse can occur at any rate.

FIGS. 29A-C illustrate another embodiment of a stabilizing structure3500. The stabilizing structure 3500 comprises a plurality of elongatedstrips 3502 arranged in parallel, and whose longitudinal length can bealigned with the longitudinal axis of a wound when placed in a wound.The stabilizing structure further comprises a plurality of interveningmembers 3504 connected to the elongated strips 3502 by a plurality ofjoints 3506. As illustrated, the plurality of intervening members 3504between adjacent elongate strips 3502 define a row of cells 3508 betweeneach pair of adjacent elongate strips.

In some embodiments, the elongated strips 3502 are rigid. In certainembodiments, the elongated strips 3502 are semi-rigid. In particularembodiments, the elongated strips 3502 are flexible. In someembodiments, the elongated strips 3502 are compressible. As illustratedin FIGS. 29A-29C, one embodiment comprises a plurality of strips thatare rigid in a vertical dimension but also are flexible and capable ofbending along their length.

In some embodiments, the intervening members 3504 are rigid. In certainembodiments the intervening members 3504 are semi-rigid. In particularembodiments, the intervening members are flexible. In some embodiments,the intervening members 3504 are compressible. As illustrated in FIG.29A-29C, one embodiment comprises intervening members in the form ofpanels equally spaced apart between adjacent strips, to define aplurality of similar-shaped (e.g., diamond-shaped) cells. In otherembodiments, the intervening members need not be equally spaced. Theintervening members may be attached to the strips by joints 3506 in theform of a hinge (e.g., a living hinge or a more flexible piece ofmaterial between the strips and the intervening members).

In some embodiments, the plurality of intervening members 3504 areconfigured to pivot relative to the elongated strips 3502 and tocollapse so as to allow the elongated strips to collapse relative to oneanother and come closer together. In some embodiments, the joints 3506are configured to pivot and collapse in only one direction. In certainembodiments, the joints 3506 are configured to pivot and collapse inboth directions, comprising a full 180 degrees of rotation relative tothe elongated strips 3502. In certain embodiments, when the jointspivot, they pivot completely so as to rest the intervening members 3504against the elongated strips 3502. In some embodiments, the joints donot pivot completely and the intervening members do not come to restagainst the elongated strips 3502.

Preferentially, in certain embodiments, by controlling the direction inwhich the pivoting occurs, the collapsed length of the stabilizingstructure 3500 can be controlled. In particular embodiments, because ofthe rigidity of the elongate strips, the cells 3508 in a row betweenadjacent elongate strips are configured to collapse together as theadjacent elongate strips 3502 collapse relative to one another. In someembodiments, one or more rows of cells 3508 between adjacent strips 3502are configured to collapse in a first direction, and one or more rows ofcells between adjacent strips 3502 are configured to collapse in asecond direction opposite the first direction. As illustrated in FIGS.29A-29C, the orientation of cells in adjacent rows alternates so thatcells of a first row collapse in a first direction, and cells of a nextrow collapse in an opposite second direction. Joints 3506 may beconfigured so that joints 3506 in adjacent rows collapse in differentdirections.

By configuring the joints 3506 and/or cells of the stabilizing structureto pivot and collapse in preferred directions, the length of thecollapsed structure can be modified. The embodiment shown in FIGS.29A-29C will have a shorter collapsed length than a structure where allthe rows of cells 3508 are configured to collapse in the same direction.Thus, the collapsed length of the structure can be controlled dependingon the orientation of the cells and the direction in which theintervening members collapse between adjacent rows. In some embodimentsas described above with respect to FIGS. 28A-28B, the stabilizingstructure preferably lengthens after collapse under negative pressure.In other embodiments, it may be preferred that the stabilizing structurenot lengthen after collapse under negative pressure.

In FIGS. 29A-29C, the intervening members 3504 in adjacent rows aregenerally aligned so that the intervening members connect to theelongate strips at approximately the same location on opposite sides ofthe strip and share the same joint 3506 location. In other embodiments,the intervening members 3504 between a first elongate strip 3502 and asecond elongate strip 3502 are offset relative to intervening members3504 between the second 3502 and a third adjacent strip 3502. In theseembodiments, the intervening members 3504 are staggered such that theydo not share the same joint 3506 location.

As shown in FIGS. 29A-29C, the enclosed cell 3508 formed by twointervening members and two sections of the elongated strips is aquadrilateral. In some preferred embodiments, the enclosed shape can bea square, rectangle, diamond, oblong, oval, and/or parallelepiped. Insome embodiments, the enclosed shape is a rhomboid. In certainembodiments the enclosed shape is a trapezoid.

In certain preferred embodiments, the joint 3506 may be configured tolimit the range of motion of the intervening member 3504, and may beused to prevent the intervening members 3504 from becoming fullyperpendicular to the adjacent strips. Thus, the joint may be configuredto pre-set the intervening members 3504 in a partially collapsedposition. For example, a lip or other portion of material at the jointmay be used to limit the angular motion of the intervening members. Thelip or other portion of material may also prevent the joint fromcollapsing completely flat. In some embodiments, the joint may beconfigured to prevent the intervening members from rotating in 180degrees along the plane formed by the strips.

In some embodiments, when the stabilizing structure 3500 is placed in awound, the elongated strips 3502 are positioned generally parallel tothe lateral edges of the wound. Preferably, the stabilizing structure isconfigured in the wound such that the elongated strips are positionedparallel to the longitudinal axis of the wound, as described withrespect to FIGS. 28A-28B above. The strips may also bend along theirlength and bow outwardly to fit within the wound. The stabilizingstructure may be cut to an appropriate size to fit the structure in thewound. In other embodiments, the elongated strips 3502 are positionedperpendicular to the edge of the wound, or may not be oriented along anyedge of the wound.

In the embodiments of FIGS. 29A-29C, as well as in other embodiments ofstabilizing structures described herein, the strips can be constructedfrom a material selected from the group consisting of silicone, rigidplastics, semi-rigid plastics, flexible plastic materials, compositematerials, biocompatible materials and foam. In some embodiments, theintervening members can be constructed from a material selected from thegroup consisting of silicone, rigid plastics, semi-rigid plastics,flexible plastic materials, composite materials, biocompatible materialsand foam. In some embodiments, the stabilizing structure is surroundedby absorbent materials. In certain embodiments the stabilizing structureis surrounded by non-absorbent materials. In some embodiments thematerial surrounding the stabilizing structure is foam. In particularembodiments, the spaces between the intervening members 3504 and theelongated strips 3502 are filled with foam.

FIGS. 30A-G illustrate an embodiment of a stabilizing structure 3600that is similar to the ones described above in relation to FIGS. 29A-Cand FIG. 28B. As illustrated in FIG. 30A, in some embodiments, thestabilizing structure 3600 comprises a plurality of elongated strips3602 connected by a plurality of intervening members 3604 at a pluralityof joints 3606. As illustrated in FIGS. 30A-G, the plurality ofintervening members comprise a plurality of bars 3604 connectingadjacent elongated strips and connected to the elongated strips at upperand lower joint locations. The plurality of joints in one embodimentcomprise a plurality of pins 3606 connected to the bars and received inupper and lower vertical openings in the strips 3602. Other types ofjoints are also contemplated, including ball joints. The bars arepreferably equally spaced within a row between adjacent elongatedstrips, and may be offset or staggered in an adjacent row, such that inan adjacent row, the bars connect to the elongate strip at a locationbetween the bars of the first row. In other embodiments, the interveningmember can comprise a wire or other elongate structure configured toextend between adjacent elongated strips.

Preferably, as illustrated in the top view of FIG. 30B and the frontview of FIG. 30C, in certain embodiments the pins cause the bars toprotrude above the vertical top and the vertical bottom of the elongatedstrips 3602. In other embodiments, the bars 3604 may be connected to theelongated strips so that they are located flush with the vertical topand vertical bottom of the elongated strips 3602. In further otherembodiments, the bars 3604 may be connected so that they are locatedbelow the vertical top of the elongated strips 3602 and above thevertical bottom of the elongated strip.

As illustrated in FIGS. 30A and 30C, the joints 3606 can preferablycomprise a plurality of stops 3608 configured to limit the rotation ofthe bars relative to the strips. The stops may protrude vertically fromthe strips to limit the movement of the bars. For example, these stopsmay be used to prevent the bars from becoming fully perpendicular withrespect to the adjacent strips, and may be used to provide apreferential direction of collapse to adjacent rows. As shown in FIG.30A, a first row may have bars angled in a first direction, and a secondrow may have bars angled in a second direction. In some embodiments,there are two stops per bar on a given strip, to restrict motion in twodirections. In other embodiments, there is one stop or three or morestops per bar on a given strip.

FIGS. 30E-G illustrate the stabilizing structure 3600 in a collapsedconfiguration. Similar to the structures of FIGS. 29A-C and FIG. 28B,the structure 3600 may be positioned in a wound in an orientationconfigured to collapse in a direction perpendicular to the longitudinalaxis of the wound. As described above, the stabilizing structure may besurrounded by or filled with absorbent material such as foam. In oneembodiment, because the vertical space between the upper and lower barsof the structure 3600 are open (as best shown in FIG. 30C), elongateblocks of foam or other compressible material may be placed in betweenadjacent strips to provide a desired compressibility as the structurecollapses.

FIG. 31 illustrates an embodiment of a stabilizing structure 3700 thatis similar to the structures described above in relation to FIG. 28B,FIGS. 29A-C and FIGS. 30A-G. In certain embodiments, the stabilizingstructure 3700 can collapse in any manner described above. The elongatedstrip 3702 as illustrated is formed in two halves, and can be separatedalong line 3708. The intervening members 3704 can be in the form ofpanels as described above. The joints 3706 on the upper half of anelongated strip may comprise pins located on opposite sides of the stripextending downward from the top of the upper half of the strip. Thejoints 3706 on the lower half of an elongated strip may comprise pinslocated on opposite sides of the strip extending upward from the bottomof the lower half of the strip. These pins may engage vertical openingslocated at the four corners of the intervening member 3704. As the upperand lower halves are brought together, the pins may engage the openingsin the panels. The upper and lower halves may be secured by any numberof mechanisms, such as with adhesive and mechanical connections.

In the FIG. 31 embodiment, with the ability to separate the two halvesof 3702 along line 3708, intervening members 3704 may be easily removedor replaced. In some embodiments, only some of the intervening members3704 are removed. In certain embodiments, alternating interveningmembers 3704 are removed. In certain preferred embodiments, interveningmembers are removed in a preferential manner so as to allow thestabilizing structure 3700 to collapse in a controlled manner mostappropriate for a particular wound. In some embodiments, the interveningmembers are replaced or removed to maximize the collapsed length of thestructure 3700. In certain embodiments, intervening members are replacedor removed to minimize the collapsed length of structure 3700. In someembodiments, intervening members are replaced or removed to attain adesired length for the collapsed structure.

FIG. 33 illustrates another embodiment of elongate strips that may beused to form a stabilizing structure, similar to that described in FIGS.8A-D. The first strip illustrated in the upper portion of FIG. 33 may bean elongate strip having a plurality of spaced apart openings extendingalong a central axis of the strip. The second strip illustrated in thelower portion of FIG. 33 may have a plurality of spaced apart notchesextending from the upper and lower edges of the second strip andseparate by a middle portion. A plurality of the first strips and aplurality of the second strips can be assembled into a stabilizingstructure similar to what's shown in FIGS. 8A, 8C and 8D, wherein theplurality of first strips are arranged in parallel to each other, andthe plurality of second strips are arranged in parallel to each other.The plurality of first and second strips engage one another by themiddle portions of the second strips positioned through the openings inthe first strips, to place the plurality of first strips at an angle tothe plurality of second strips. This structure is configured to collapsein a horizontal plane while remaining rigid in the vertical plane.

FIG. 34 illustrates an embodiment of a stabilizing structure similar tothe embodiment of FIG. 13 described above. A plurality of longitudinalstrips can be provided each in the form of a wavy strip that, whenjoined face-to-face, form one or more circular or ovoid cells. Theentire structure can be collapsed into a substantially flatconfiguration, and can be contained within a roll. To use thestabilizing structure, a portion of the structure can be unrolled andcut at a desired length. Preferably, as the stabilizing structure isunrolled it expands to its natural, deployed configuration. It will beappreciated that other embodiments of the stabilizing structure, and notjust embodiments using the wavy strips of FIG. 13 , may be assembledinto a rolled configuration.

FIG. 35 illustrates another embodiment of a stabilizing structure. Inthis embodiment, the stabilizing structure has an elongated, preferablyoval shape, wherein cells within the oval shape have a plurality ofcells arranged in a plurality of concentric rings. In the embodimentillustrated, a central oval cell is surrounded by two oval-shaped rings.Other embodiments, can include more than two oval-shaped rings.

While the invention has been described in connection with specificmethods and apparatuses, those skilled in the art will recognize otherequivalents to the specific embodiments herein. It is to be understoodthat the description is by way of example and not as a limitation to thescope of the invention and these equivalents are intended to beencompassed by the claims set forth below.

Features, materials, characteristics, or groups described in conjunctionwith a particular aspect, embodiment, or example are to be understood tobe applicable to any other aspect, embodiment or example describedherein unless incompatible therewith. All of the features disclosed inthis specification (including any accompanying claims, abstract anddrawings), and/or all of the steps of any method or process sodisclosed, may be combined in any combination, except combinations whereat least some of such features and/or steps are mutually exclusive. Theprotection is not restricted to the details of any foregoingembodiments. The protection extends to any novel one, or any novelcombination, of the features disclosed in this specification (includingany accompanying claims, abstract and drawings), or to any novel one, orany novel combination, of the steps of any method or process sodisclosed.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of protection. Indeed, the novel methods and systems describedherein may be embodied in a variety of other forms. Furthermore, variousomissions, substitutions and changes in the form of the methods andsystems described herein may be made. Those skilled in the art willappreciate that in some embodiments, the actual steps taken in theprocesses illustrated and/or disclosed may differ from those shown inthe figures. Depending on the embodiment, certain of the steps describedabove may be removed, others may be added. Furthermore, the features andattributes of the specific embodiments disclosed above may be combinedin different ways to form additional embodiments, all of which fallwithin the scope of the present disclosure.

Although the present disclosure includes certain embodiments, examplesand applications, it will be understood by those skilled in the art thatthe present disclosure extends beyond the specifically disclosedembodiments to other alternative embodiments and/or uses and obviousmodifications and equivalents thereof, including embodiments which donot provide all of the features and advantages set forth herein.Accordingly, the scope of the present disclosure is not intended to belimited by the specific disclosures of preferred embodiments herein, andmay be defined by claims as presented herein or as presented in thefuture.

What is claimed is:
 1. A stabilizing structure for insertion into awound, comprising: a collapsible stabilizing structure comprised atleast partially of foam and having a plurality of cells in a plane, eachcell having at least one wall wherein the stabilizing structure has alength and a width wherein at least three cells extend in a widthdirection and at least one planar support structure within thestabilizing structure extends in a direction perpendicular to the planeand is parallel to an axis along the length of the stabilizingstructure, each cell having a top end and a bottom end with an openingextending through the top and bottom ends in a direction perpendicularto the plane; wherein the stabilizing structure has an outer wall forcontacting tissue of the wound and is configured to collapsesignificantly more within the plane than along the directionperpendicular to the plane upon application of negative pressure to thewound; and wherein the cells are configured to collapse more in theplane along the width direction than along the length of the stabilizingstructure such that opposing edges of the wound collapse towards closureof the wound.
 2. The stabilizing structure of claim 1, wherein the atleast one planar support structure extends in a vertical direction uponinsertion of the stabilizing structure into the wound.
 3. Thestabilizing structure of claim 1, wherein the width direction isperpendicular to the axis along the length.
 4. The stabilizing structureof claim 1, wherein the stabilizing structure comprises a plurality offirst strips extending at least partially along the axis and a pluralityof intersecting strips extending in the second direction perpendicularto the axis.
 5. The stabilizing structure of claim 1, wherein separateporous material layers are provided above, below, or on both upper andlower layers of the stabilizing structure.
 6. The stabilizing structureof claim 5, wherein the porous material layers comprise a foam.
 7. Thestabilizing structure of claim 1, wherein the stabilizing structure isin the shape of an oval.
 8. A stabilizing structure for insertion into awound, comprising: a plurality of elongate strips arranged generally inparallel along a length of the stabilizing structure wherein at least aportion of each elongate strip has a planar shape; and a plurality ofintervening members connecting the elongate strips, wherein theplurality of intervening members are configured to pivot relative to thestrips to allow the plurality of elongate strips to collapse relative toone another along a width of the stabilizing structure, the elongatestrips and intervening members defining cells such that the stabilizingstructure has at least three cells extending along the width of thestabilizing structure; wherein the intervening members between a firststrip and a second strip are configured to pivot independently of theintervening members between a second strip and a third strip such thatthe cells collapse more along the width than along the length of thestabilizing structure upon application of negative pressure to thewound.
 9. The stabilizing structure of claim 8, wherein the interveningmembers are connected to the elongate strips via at least one joint. 10.The stabilizing structure of claim 9, wherein the elongate stripsinclude planar walls and the joint comprises a hinge.
 11. Thestabilizing structure of claim 8, wherein the plurality of interveningmembers between adjacent elongate strips define a row of cells betweeneach pair of adjacent elongate strips, the intervening memberscomprising one or more walls.
 12. The stabilizing structure of claim 11,wherein the cells in a row between adjacent elongate strips areconfigured to collapse together as the adjacent strips collapse relativeto one another.
 13. The stabilizing structure of claim 8, whereinseparate foam layers are provided above, below, or on both upper andlower layers of the stabilizing structure.